The semiconductor industry has experienced rapid growth due to continuous improvements in the integration density of various electronic components (i.e., transistors, diodes, resistors, capacitors, etc.). For the most part, this improvement in integration density has come from gradual reductions in minimum feature size, which allows more of the smaller components to be integrated into a given area. These smaller electronic components also require smaller packages that utilize less area than previous packages. Some smaller types of packages for semiconductor components include quad flat packages (QFPs), pin grid array (PGA) packages, ball grid array (BGA) packages, and so on.
The integrated fan-out packages are powerful solutions for heterogeneous integration between chips and system. The improved routability and reliability provided by the integrated fan-out packages are key factors for future packages. How to simplify the fabricating process of the integrated fan-out packages is an important issue.